K20 K20Z3 06-11 Honda Civic Si FG1 FD FA K-Series Tri-Y 2.5" Header Exhaust 2.0L 8th Gen FA5K20Z3 06 11 Honda Civic Si FG1 FD FA K Series Tri Y 2. 5" Header Exhaust 2. 0L USA Civic Si K series FG FD FA Tri Y header featuring a true step up exhaust header design. The Tri Y header delivers low to mid end power while utilizing a four piece design which maximizes the engine compartment space. This exhaust manifold is ideal for all forms of competition; Autocross, drag racing and road racing. These also include Gaskets & all necessary hardware